Wheelchair ramps comprising an inclined plane are often installed to permit wheelchair users, as well as people pushing strollers, carts, or other wheeled objects, to more easily access a vehicle such as a van or public transportation.
Ramps must be carefully designed in order to be useful. Many jurisdictions have established standards for wheelchair ramps. For example, they may specify the minimum width of a wheelchair ramp is 36 inches, and the slope must not be steeper than 1 inch of rise for every 12 inches of length. A less steep rise can be easier for a wheelchair user to navigate, as well as safer in icy climates.
Wheelchair ramps come in a number of varieties each intended for a different purpose. There are permanent, semi-permanent and portable. Permanent ramps are designed to be bolted or welded in place. Portable ramps are lightweight, usually aluminum and typically fold for ease of transport. Wheelchair ramps (or other ways for wheelchair users to gain access) are required for public accommodations in the U.S. by the Americans with Disabilities Act. Similar solutions are also needed by wheelchair users to gain access to private vehicles.
What is needed is a cost effective solution to transporting a wheelchair in a vehicle using a folding ramp that mounts to the vehicle's trailer hitch. A preferred device should fold such that it does not obstruct visibility through the back window. The ramp should also be mounted outside the vehicle, to conserve interior room, but not obstruct the operation of the rear door.